JP7088141B2 - Metal-plated steel pipe manufacturing method and molten metal plating equipment for steel pipes - Google Patents

Description

The present invention relates to a method and an apparatus for manufacturing a metal-plated steel pipe applied to piping applications such as water, gas, and oil. Regarding the method and equipment for applying plating.

Metal-plated steel pipes, for example, zinc-plated steel pipes, are manufactured by immersing pretreated steel pipes (defatting, pickling and chemical conversion treatment) in a hot-dip galvanized bath for a certain period of time. Then, air or steam is blown onto the inner and outer surfaces of the steel pipe lifted from the plating bath to blow off the molten zinc excessively adhering to the steel pipe, and after cutting the hot-dip zinc dripping, the steel pipe is immersed in a water cooling tank and cooled. Processing is applied. Conventionally, many efficient methods have been proposed for removing excess zinc on the inner and outer surfaces of steel pipes pulled up from the hot-dip galvanizing bath while ensuring quality.

For example, in Patent Document 1, while the steel pipe being lifted passes through the outer surface blower, the mandrel rod is passed through the steel pipe, and the compressed gas is injected from the injection nozzle to remove the excess zinc on the inner surface of the steel pipe. A technique is disclosed in which the plating thickness can be made uniform by a method of blowing out.

Further, in the technique disclosed in Patent Document 2, from the viewpoint of reducing the manufacturing cost, after the steel pipe is immersed in the molten zinc bath, the excess of the outer surface of the steel pipe is generated by the compressed gas in the process of pulling the steel pipe from the molten zinc bath in the longitudinal direction. In the method of removing zinc and then removing excess zinc on the inner surface of the steel pipe with compressed gas, the molten zinc bath is set to a low temperature, and the outer surface of the steel pipe is pulled up from the molten zinc bath in the longitudinal direction by the compressed gas. A method has been proposed in which the steel pipe is heated to a temperature higher than the molten zinc bath temperature after the excess zinc is removed, and the excess zinc on the inner surface of the steel pipe is removed by a compressed gas.

Further, from the viewpoint of improving productivity, Patent Document 3 describes that a steel pipe is preheated to 100 to 600 ° C., then immersed in a hot-dip metal plating bath at 430 to 480 ° C. for 20 to 100 seconds for plating, and then melted. A method of pulling up a plated steel pipe in a galvanized bath and controlling the amount of external plating adhered to the plated steel pipe is disclosed. By preheating the steel pipe, the amount of heat required to maintain the bath temperature in the plating tank can be reduced.

Japanese Unexamined Patent Publication No. 2011-63844 Japanese Unexamined Patent Publication No. 5-140722 Japanese Unexamined Patent Publication No. 11-2469559

However, the above-mentioned conventional technique still has the following problems to be solved. In the above-mentioned prior art, various techniques related to quality and productivity are disclosed as a method for manufacturing zinc-plated steel pipes, but operational stability is an important issue regarding productivity when the steel pipes are immersed in a metal plating bath. No details of sex are disclosed.

The present invention has been made in view of the above circumstances, and an object thereof is to propose a method for stably producing a metal-plated steel pipe when the steel pipe is immersed in a metal-plated bath, and is suitable for the method. The present invention is to provide a molten metal plating apparatus for steel pipes.

As a result of diligent studies to solve the above-mentioned problems, the inventors have found a method for stabilizing the operation of a metal-plated steel pipe and a device suitable for the method. The present invention developed in order to solve the above problems and realize the above object is as shown in the following gist structure. That is, in the present invention, first, in a method of immersing a steel pipe in a molten metal plating bath for a certain period of time and then pulling it out of the plating bath to manufacture a metal plated steel pipe, a screw having a spiral surface on a rotating shaft is used. The steel pipe is lowered and transported into the molten metal plating bath and immersed in the steel pipe, and the steel pipe that has passed through the spiral surface end portion is held on the cradle, and the payout device installed at the spiral surface end portion of the rotating shaft rotates. When the steel pipe on the cradle is discharged to the lifting position and the steel pipe is pulled out from the plating bath by the lifting device, after the steel pipe discharged by the dispensing device reaches a predetermined position and from the steel pipe. We propose a method for manufacturing a metal-plated steel pipe, which comprises raising the lifting device before the position of the steel pipe becomes unstable due to the flow of the plating bath due to the rotation of the payout device.

Regarding the method for manufacturing a metal-plated steel pipe according to the present invention,
a. When the rotation angle θ _A of the payout device is in the range of more than −45 ° and less than 70 °, the lifting device is raised, where θ _A is 0 when the payout device and the longitudinal direction of the steel pipe are orthogonal to each other. °, and the direction of rotation is positive,
b. The ratio h / D of the height difference h (m) between the upper end of the payout device and the lower end of the steel pipe on the cradle with respect to the steel pipe diameter D (m) is made larger than 0.4.
c. The molten metal plating bath is composed of one selected from molten zinc, molten aluminum, molten zinc alloy, molten aluminum alloy and molten zinc-aluminum alloy.
d. The steel pipe to be subjected to hot metal plating is a welded steel pipe or a forge welded steel pipe.
Can be a more preferred solution.

Secondly, the present invention includes a plating tank constituting a molten metal plating bath, a screw having a helicoid surface on a rotating shaft for lowering and immersing a steel tube in the molten metal plating bath, and a helicoid of the screw. A cradle for temporarily receiving the steel pipe that has passed through the surface end portion, a dispensing device for the steel pipe provided at the spiral surface end portion of the rotating shaft, and the steel pipe on the cradle discharged by the dispensing device. Provided is a molten metal plating apparatus for a steel pipe, comprising a lifting device for lifting, and having a mechanism for controlling the ascent of the lifting device in synchronization with the rotation angle of the payout device.

Regarding the molten metal plating apparatus for steel pipes according to the present invention,
e. The cradle has an inclined portion, a temporary standby portion, a mountain portion, and a positioning portion arranged from the rotation axis of the screw toward the lifting device.
The upper end of the payout device is above the apex of the mountain portion of the cradle, and the difference in height h (m) is a ratio of the diameter D (m) of the steel pipe to be dispensed, h / D to 0. Arranged so that it is larger than 4
Can be a more preferred solution.

As described above, according to the present invention, a screw is used as a device for immersing a steel pipe in a plating tank, and plating in the plating tank is performed by optimizing the lifting timing of the plated steel pipe and optimizing the shape of the dispensing device. It is possible to avoid defective pulling of steel pipes and to stabilize operations.

It is a manufacturing flow diagram which shows one Embodiment of this invention. It is a top view of the molten metal plating apparatus of a steel pipe which shows one Embodiment of this invention. It is AA'view side view of the molten metal plating apparatus of a steel pipe which shows the said embodiment. It is a BB'viewing bottom view of the molten metal plating apparatus of the steel pipe which shows the said embodiment, and is the enlarged view of the state which the steel pipe is loaded on the helicoid, and (b) the steel pipe is in the position of a lifting apparatus. It is an enlarged view of the vicinity of a screw after being dispensed. It is a graph which shows the relationship between the rotation angle θ _A of the payout device which concerns on the said embodiment, and the occurrence rate of withdrawal defects. FIG. 3 is a CC'enlarged front view of the vicinity of the lifting device according to the above embodiment. It is a graph which shows the influence of the ratio h / D of the height difference h between the upper end of a lifting device and the lower end of a steel pipe which concerns on the said embodiment with respect to a steel pipe diameter D on the occurrence rate of a lifting failure.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The present invention is not limited to this, and the present invention can be appropriately modified and carried out without changing the gist thereof.
As an example of the outline of the processing process in the present invention, FIG. 1 shows a manufacturing flow of a hot-dip galvanized steel pipe. The steel pipe is subjected to degreasing, pickling, and chemical conversion treatment in the pretreatment step, and then dried and immersed in a zinc plating bath in a plating tank of a hot-dip galvanizing apparatus for a certain period of time. Next, the steel pipe is lifted from the plating bath, and when it is lifted, air or steam is blown onto the inner and outer surfaces of the steel pipe to remove the excessively adhered molten zinc and adjust the plating adhesion amount. After that, the steel pipe is cooled in a cooling tank. Finally, the galvanized steel pipe will be inspected before shipping. Here, a zinc-plated steel tube is shown as an example, but as molten metal plating, molten zinc or molten aluminum, 5% aluminum-zinc plating as a molten zinc alloy, 55% aluminum-zinc plating as a molten aluminum alloy, etc. , Molten zinc-aluminum alloy is exemplified, and the molten metal may contain unavoidable impurities in addition to magnesium, silicon, and iron.

The top view and the AA'view side view of the molten metal plating apparatus for a steel pipe showing an embodiment of the present invention are shown in FIGS. 2 and 3, respectively. Further, FIG. 4 is a bottom view of BB'of the molten metal plating apparatus shown in FIGS. 2 and 3, in which (a) an enlarged view of a state in which the steel pipe 2 is loaded on the spiral surface of the screw, and (B) An enlarged view of the vicinity of the screw after the steel pipe 2 is dispensed to the position of the lifting device 5 is shown. Further, FIG. 6 shows a CC'enlarged front view of FIG. 4 (b) in the vicinity of the lifting device. The method of the present invention will be described with reference to FIGS. 2 to 4 and FIG. The pretreated steel pipe 2 is conveyed from the bottom side to the top side of the plating tank 1 and mounted on the spiral surface 32 of the screw 3 having the spiral surface 32 on the rotating shaft 31. FIG. 2 shows an example of a molten metal plating apparatus capable of horizontally and descending two steel pipes 2 into a plating tank 1 at the same time. The steel pipe 2 is supported by the center guide 6 and the side guide 9 so as not to come off from the spiral surface 32 of the screw 3.

The steel pipe 2 is carried down to the lower part of the plating tank 1 by the rotation of the plurality of screws 3 rotating in synchronization, and is immersed in the molten metal plating bath Z in the plating tank 1 to be subjected to the molten metal plating treatment. As shown in FIG. 3, the steel pipe 2 is held by the screw 3 with a low top side (tip) and a high bottom side (tail end) during downward transportation, and the steel pipe 2 is immersed in the plating bath Z while being immersed in the steel pipe. The air in 2 can be exhausted. Although FIG. 3 shows an example in which the tip end side of the steel pipe 2 is immersed in the plating bath first, the tail end side may be immersed in the plating bath first. The steel pipe 2 is not only lowered by the rotation of the screw 3, but also the dipping position in the plating tank is fixed by the skid plate 8 in order to fix the dispensing position.

The steel pipe 2 lowered and conveyed to the lower part in the plating tank 1 by the rotation of the screw 3 reaches the helicoid end portions 11 and 12 and then lands on the cradle 4. After that, the steel pipe 2 is sequentially dispensed in the direction of the lifting device 5 (the payout direction in FIG. 2) by the payout device 10 installed on the rotating shaft 31 of the screw 3. The payout device 10 rotates around the rotating shaft 31 to push the steel pipe 2 toward the lifting device 5. As in the present invention, by installing a payout device 10 for discharging the steel pipe 2 to the lifting device 5 at the spiral surface end portions 11 and 12 of the rotary shaft 31 of the screw 3, the steel pipe 2 is immersed in the plating bath Z. It is possible to perform the payout with one device, which is advantageous in terms of maintainability, which is preferable.

The discharged steel pipe 2 is lifted from the plating bath Z by being placed on the support portions 51 of the plurality of lifting devices 5 and then raised by the support portions 51. At the time of salvage, the steel pipe 2 is tilted by being loaded on the support portions 51 of the plurality of salvage devices 5, so that the molten metal in the steel pipe can be easily discharged.

In the molten metal plating apparatus shown in FIGS. 2 and 3, three screws 3 are installed in the horizontal transport direction (longitudinal direction of the steel pipe) with respect to one steel pipe. At least two screws 3 are required to stabilize the posture of the steel pipe 2, but in the case of two screws, the posture of the steel pipe 2 to be carried down immediately after the plating bath Z is charged may become unstable. It is desirable to install three or more pipes because it is expensive and the steel pipe 2 may bend and the air inside the steel pipe may not be sufficiently exhausted.

The inventors rotate the payout device 10 installed at the lower ends 11 and 12 of the spiral surface of the screw 3 in the molten metal plating device, and when paying out the steel pipe 2 on the cradle to the pulling device 5 side, the lifting device. Regarding the start time of withdrawal of No. 5, the influence of the rotation angle of the payout device 10 on the withdrawal failure of the steel pipe was investigated.

The rotation angle θ _A of the payout device 10 at the time of payout is an angle orthogonal to the longitudinal direction of the steel pipe 2 when the steel pipe 2 is paid out from the payout device 10 to the lifting device 5 side as shown in FIG. 4 (b). θ _A = 0 °, and the rotation traveling direction 13 of the lifting device 5 was defined as positive. As an example, FIG. 5 shows the relationship between the rotation angle θ _A of the payout device 10 and the rate of occurrence of repatriation defects of the plated steel pipe 2 at a steel pipe diameter of 50 A. The withdrawal defect occurrence rate is counted for the number of bends, scratches, withdrawal troubles, etc. that occur in the plating tank 1 for the steel pipe 2 that was withdrawn from the zinc plating apparatus when the steel pipe 2 was galvanized. , Calculated as a ratio to the total number of processed pieces. When the withdrawal start timing is −45 ° or less at the rotation angle θ _A of the withdrawal device 10 , the amount of the steel pipe 2 withdrawn is insufficient and the load is often not properly loaded on the support portion 51 of the withdrawal device. The rate of poor withdrawal will be very high. On the other hand, when the withdrawal start timing exceeds 70 ° at the rotation angle θ _A of the payout device 10 , a flow is generated in the plating bath Z due to the rotation of the payout device 10 away from the withdrawal device 5 , and the withdrawal device 5 Phenomenon that the steel pipe 2 discharged to the side moves to the screw side before the start of withdrawal, or if the apparent specific gravity of the steel pipe is low, it comes off from the support portion 51 during withdrawal. Since it occurs with a certain probability, the rate of defective withdrawal increases. From FIG. 5, it can be seen that it is preferable to start the lifting device 5 ascending when the rotation angle θ _A of the payout device 10 is in the range of more than −45 ° and less than 70 °. Here, in order to further reduce the defect rate, it is desirable that the rotation angle θ _A of the payout device 10 is in the range of more than −20 ° and less than 25 °.

From the above results, the withdrawal start time of the withdrawal device 5 is after the steel pipe 2 dispensed by the payout device 10 reaches a predetermined position, and the payout device 10 moves away from the steel pipe 2. It is necessary before the position of the steel pipe 2 becomes unstable due to the flow of the plating bath due to rotation. "The steel pipe reaches a predetermined position" means that the steel pipe 2 is in a state where it can be lifted. As shown in FIG. 6, the shape of the cradle 4 is positioned to match the inclined portion 41 from directly below the screw toward the lifting device 5 , the temporary standby portion 42 of the steel pipe, the mountain portion 43 , and the supporting portion 51 of the lifting device 5. In the case of the portion 44 , it is necessary to start the ascending of the lifting device 5 after the discharged steel pipe 2 has passed at least the apex of the mountain portion 43 . Otherwise, the steel pipe 2 may not be placed on the support portion 51 when the lifting device 5 is lifted. Further, "the position of the steel pipe becomes unstable" means that the steel pipe 2 once discharged to the lifted position on the cradle 4 is plated, for example, caused by the movement of the dispensing device 10 moving away from the steel pipe 2 . Due to the flow in the bath Z , it moves from the lifting position and is not loaded on the support portion 51 at the start of lifting of the lifting device 5 , or the steel pipe 2 loaded on the support portion 51 swings while rising. Therefore, there is a case where the support portion 51 is detached from the support portion 51.

Next, the inventors confirmed the influence of the arrangement and shape of the payout device 10 . As shown in FIG. 6, the difference in height from the upper end of the payout device 10 in the height direction to the lower end of the steel pipe 2 on the cradle 4 is h, the diameter of the steel pipe 2 is D, and the steel pipe 2 is on the cradle 4. We confirmed the relationship between h / D and the rate of poor salvage when the product is at the highest position (top 43). As an example, FIG. 7 shows the relationship between h / D and the rate of occurrence of repatriation defects at a steel pipe diameter of 50 A. As is clear from FIG. 7, when the h / D is 0.4 or less, the rate of defective repatriation deteriorates. It is presumed that the reason for this is that the payout device 10 did not come into contact with the correct position of the steel pipe 2 and the steel pipe 2 was not pushed out to the lifting device 5 side. From the above results, it is necessary to set h / D> 0.4. Although the upper limit of h / D is not particularly set, it is sufficient if the side surface of the payout device 10 comes into contact with the steel pipe 2 , and if the h / D is taken too large, the payout device 10 becomes too large. Degree is enough.

The apparatus according to a preferred embodiment of the present invention comprises a plating tank 1 constituting a molten metal plating bath Z and a rotary shaft 31 for lowering and transporting a steel tube 2 into the molten metal plating bath Z and immersing the steel pipe 2 in the hot metal plating bath Z. A screw 3 having a helicoid surface 32, a cradle 4 for temporarily receiving the steel pipe 2 that has passed through the helicoid end portions 11 and 12 of the screw 3, and the spiral surface end portion of the rotating shaft 31. It is composed of a payout device 10 of the steel pipe 2 and a lifting device 5 for pulling up the steel pipe 2 on the cradle 4 paid out by the payout device 10, and is synchronized with the rotation angle θ _A of the payout device 10. This is a molten metal plating device having a mechanism for controlling the ascent of the lifting device 5.

It is preferable that the device for controlling the ascent of the lifting device 5 is set to start the pulling of the steel pipe 2 when the rotation angle θA of the payout device 10 is within a predetermined range. It is more preferable to start ascending the lifting device 5 when the rotation angle θA of the payout device 10 is in the range of more than −45 ° and less than 70 °, and the rotation angle θA of the payout device 10 exceeds −20 °. It is more preferably in the range of less than 25 °. The reason is based on the above.

Further, in the cradle that temporarily receives the steel pipe that has passed through the end of the spiral surface of the screw, as shown in FIG. 6, the inclined portion 41 in which the steel pipe rolls and moves, the temporary standby portion 42 of the steel pipe, the mountain portion 43, and the steel pipe. It is preferable that the positioning portion 44 for lifting the pipe is provided, and the positioning portion 44 is arranged in this order from directly below the screw 3 to the position of the lifting device 5. The upper end of the payout device 10 is above the apex 43 of the mountain portion of the cradle 4, and the difference in height h (m) is the ratio h (m) to the diameter D (m) of the steel pipe 2 to be paid out. It is preferable that the / D is arranged so as to be larger than 0.4. The reason is based on the above.

In FIGS. 2 and 3, the arrangement of the screws installed in the metal plating apparatus is described as an example in the case of two rows, but depending on the size of the steel pipe, it is possible to install one row or two or more rows. , The number of rows of screws is not particularly limited.

The method of the present invention can be suitably applied to forge welded steel pipes and welded steel pipes as raw pipes. The forge-welded steel pipe refers to a steel pipe formed into a pipe by heating a steel strip material, for example, the entire hot-rolled steel strip, and then hot-forming the seam portion by forge welding. The welded steel pipe is a so-called electric resistance pipe, in which a steel strip material, for example, a hot-rolled steel strip is formed into a tubular shape by a molding machine, and a seam is welded at high speed by a high-frequency welder.

(Manufacturing Example 1)
Hot-dip galvanizing of steel pipes was performed in the production flow shown in FIG. Regarding the arrangement of each device in the plating tank, it was installed in the arrangement shown in FIGS. 2 and 3. Here, the plating tank used was an internal method having a length of 7 m, a width of 2 m, and a depth of 5 m, and the length of the steel pipe was 5 m. When the steel pipe diameter was 50 A, the screw rotation speed was about 9 rpm, and the immersion time of the steel pipe in the plating bath was 2 to 3 minutes.

Table 1 shows the results of the rate of failure in lifting when the galvanizing treatment is performed by changing the rotation angle θ _A of the payout device at the start of lifting of the steel pipe. Here, the steel pipe diameter D is in the range of 30A to 200A, and the height difference h between the upper end of the lifting device and the top of the cradle peak and the ratio h / D to the steel pipe diameter D is 0.2 to 0.9. The range was set. The rate of failure in withdrawal is calculated by counting the number of bends, scratches, and withdrawal troubles that occur in the plating tank for the steel pipes that have been withdrawn from the zinc plating equipment when the steel pipes have been galvanized. Calculated as a ratio to the number.

By performing the treatment of the example of the present invention as shown in Table 1, it was clarified that the occurrence of pulling defects in the hot-dip galvanizing treatment of the steel pipe was significantly reduced, and the productivity was improved.

(Manufacturing Example 2)
Hot-dip galvanizing was performed under various h / D conditions in order to investigate the influence of the arrangement and shape of the lifting device using the same device as in Production Example 1. Here, the steel pipe diameter D was set in the range of 30 A to 200 A, and the rotation angle θ _A of the payout device at the start of pulling up the steel pipe was set in the range of −70 ° to 80 °. Table 2 shows the ratio h / D of the height difference h between the upper end of the lifting device and the top of the cradle peak and the steel pipe diameter D, and the result of the failure rate of lifting. The occurrence rate of withdrawal defects was investigated in the same manner as in Production Example 1.

As shown in Table 2, by performing the treatment of the example of the present invention, it was clarified that the occurrence of pulling defects in the hot-dip galvanizing treatment of the steel pipe was significantly reduced, and the productivity was improved.

The present invention can be applied not only to steel pipes but also to other metal pipes and the like. Further, it is suitable not only for hot-dip galvanizing but also for various hot-dip metal plating.

1 Plating tank 2 Steel pipe 3 Screw 31 Rotating shaft 32 Helicoid 4 Cradle 41 Inclined part 42 Temporary standby part of steel pipe 43 Mountain part 44 Steel pipe positioning part 5 Lifting device 51 Lifting device support 6 Center guide 7 Stopper 8 Skid Plate 9 Side guide 10 Dispensing device 11 Helicoid end 1
12 Helicoid end 2
13 Screw rotation direction 1
14 Screw rotation direction 2
Z Molten metal plating bath

Claims (5)

In a method of immersing a steel tube in a molten metal plating bath and then pulling it out of the plating bath to manufacture a metal plated steel tube, the steel tube is transported downward into the molten metal plating bath using a screw having a helicoid on a rotating shaft. The steel pipe that has passed through the end of the helicoid surface is held on the cradle, and the steel pipe on the cradle is discharged to the lifting position by the rotational operation of the dispensing device installed at the end of the helicoid surface of the rotating shaft. When pulling the steel pipe out of the plating bath by the lifting device,
The inclined portion, the temporary standby portion, the mountain portion and the positioning portion of the cradle are arranged in order from the rotation axis of the screw toward the lifting device.
The upper end of the payout device is placed above the apex of the mountain portion of the cradle, and the ratio of the height difference h (m) to the diameter D (m) of the steel pipe to be dispensed, h / D is larger than 0.4. death,
After the steel pipe discharged by the payout device reaches a predetermined position, and the steel pipe moves from the lifted position due to the flow of the plating bath due to the rotation of the payout device away from the steel pipe, or the above. A method for manufacturing a metal-plated steel pipe, which comprises raising the lifting device before the steel pipe is disengaged from a support portion of the lifting device. When the rotation angle θ _A of the payout device is in the range of more than −45 ° and less than 70 °, the lifting device is raised, where θ _A is when the payout device and the longitudinal direction of the steel pipe are orthogonal to each other. The method for manufacturing a metal-plated steel tube according to claim 1, wherein the temperature is 0 ° and the direction of rotation is positive. The metal according to claim 1 or 2 , wherein the molten metal plating bath comprises one selected from molten zinc, molten aluminum, molten zinc alloys, molten aluminum alloys and fused zinc-aluminum alloys. Manufacturing method of plated steel pipe. The method for manufacturing a zinc-plated steel pipe according to any one of claims 1 to 3, wherein the steel pipe to be subjected to hot metal plating is a welded steel pipe or a forge welded steel pipe. The plating tank that constitutes the molten metal plating bath and
A screw having a helicoid surface on the axis of rotation for lowering and immersing the steel pipe in the molten metal plating bath,
A cradle for temporarily receiving the steel pipe that has passed through the end of the helicoid surface of the screw, and
The steel pipe dispensing device provided at the end of the helicoid surface of the rotating shaft, and
It consists of a lifting device for lifting the steel pipe on the cradle that has been dispensed by the dispensing device.
The cradle has an inclined portion, a temporary standby portion, a mountain portion, and a positioning portion arranged in order from the rotation axis of the screw toward the lifting device.
The upper end of the payout device is above the apex of the mountain portion of the cradle, and the difference in height h (m) is a ratio of the diameter D (m) of the steel pipe to be dispensed, h / D to 0. Arranged so that it is larger than 4
A molten metal plating apparatus for a steel pipe, comprising a mechanism for controlling the ascent of the lifting apparatus in synchronization with the rotation angle of the dispensing apparatus.

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